Wound bobbin



May 25 1926. 1,586,181 M. CURRY WOUND BOBBI N Filed Feb. 5, i926 11.......mu l, I l I www ATTORNEYS Patented May 25, i926.

UNITEDSTATES PATENT OFFICE.

IALCOLI CURRY, OF SCARSDALE, NEW YORK, ASSIGNOR TO THE AMERICAN THREAD COMPANY, F NEW YORK, N. Y., A CORPORATION OF NEW JERSEY. j

wourm BOBBIN.

Application led February 8, 1926. Serial No. 85,670.

plied disks into which the thread may slipl so as to catch. This liability is partly due to the change of the form 4of the end surface of the mass during the pressin operation, and

to the tendency of these en surfaces to re-l turn to their original shape. In my improved bobbins I avoid this by retaining substantially the end shapes as originally wound and making the end pieces conform approxil0 mately thereto.

Inthose earlier bobbins also the end of the tube makes frictional contact with the end walls of the bobbin holders', tending to hold the outer faces of the end pieces out of enu gagement with those walls, and thus concentrating the retarding friction more particularly at surfaces whlch are of comparatively small diameter and liable to be somewhat uneven. I have found it of advantage to have the frictional contact occur at points more remote from the axis, i. e., at points alpproximately midway between the core and t e outer edges of the disks. This provides a more eicient friction and a smoother friction surface.

The objects of my invention are to attain these results.

The following is a description of my invention, reference being had to the accompanying drawings, in which,

Flg. 1 shows my improved bobbin at one stage of its manufacture;

Fi 2 shows a cross-section of a complete bobbln embodying my invention; and

Fig. 3 shows an end view of the same.

Referring more particularly to the drawin 2 is a tubular core made of aper or otr suitable material upon which 1s wound a mass of thread 4, the wind being the well known universal wind. This mass is wound so that its end surfaces between the core and periphery bulge slightly as at 6. 8 are perforated end disks of cardboard or pre-formed and applied, not only is the fricother suitable material which are, before application, pressed so as to have the concavoconvex form shown in Fig. 1, i. e., so that the portion between the perforation and the edge of the disk bulges outwardly, the concavo-convex surface engaging and conforming more or less to the outward bulges on the ends of the mass. The portion of each disk, in the zoneimmediately adjacent to the perforation, is preferably flat, as shown at 10, and before application the curvature of the bulge in the disk adjacent to the periphery thereof vas at 12 is sllghtly sharper than the corresponding bulge on the end of the mass, with the result that when the disks are forced downward so as to contact with the end of the mass, as shown in Fig. 2, they are placed under a spring tension which holds the same in close contact with the periphery of the adjacent end surface of the mass.

In forming the bobbin of Fig. 2 the parts are assembled as in Fig. 1, with a mass of thread 4 universally wound on the core 2', and pressure is then applied to the disks forcing them into close contact with the mass, and preferably slightly compressing the mass, whereupon the ends of the core are turned over as shown at 14, holding the parts together.

The bulging of the end pieces provides a central re-entrant portion 15 lying within the highest elevation 16 of the end disks so that the turned over ends of the core are within the central recesses, with the result that the contact between the bobbin holder and the ends of the bobbin is at the highest point 16, resulting in a friction drag at that distance from the center. The turned over ends of the core are thus held out of engagement with the bobbin holder.

Wlth the mass so wound and the disks so tional contact between the wound bobbin and the bobbin holder at a point removed from the core, but if the lmass for any reason expands axially, it tends to expand uniformly and the ends, as well as the disks, tend to retain theorginal curvatures of the completed product, so that the disks, such expanding notwithstanding, are held in contact with the outer peripheries of the end surfaces of the mass, thus preventing the formation of any opening such as hereinbefore referred to.

The smaller normal radius of curvature of the formed disks co-operates in producing tags and the like, but obviously other materials having similar formingl and springlike qualities may be used. For commercial purposes I prefer the heavy paper on account of its low cost, and also on account of the eiiicient friction surfaces provided.

I prefer to secure the end pieces by crimping over the ends of the core as described, but my invention is not limited tojthis means of holding the end pieces.

As will be evident to those skilled in the art, my invention permits of various modifications without departing from the spirit thereof or the scope of the appended claims.

What I claim is:

1. In a wound bobbin the improvement which consists in a mass of thread wound upon a tubular core and havin end surfaces between the core and its perip ery protruding beyond the portions 'adjacent to the core and the periphery, and disks having annular concave sur aces engaging said protruding surfaces, the disks being secured to said core and held adjacent to said mass.

2. In a wound bobbin the improvement which consists in a mass of'thread wound upon a tubular core and having end surfaces between the core and its periphery protruding beyond the portions adjacent to the core and the periphery, and disks having annular concavo-convex surfaces, the concave surfaces engaging said protruding surfaces, the disks being secured to said core and held adjacent to said mass, the disk` tending to assume a shape in whlch the radial curve of its concave surface 1s slightly A truding surfaces, the disks upon a tubular core and having a protruding end surface between the core and lts periphery and dlsks havlng annular eoncavo-convex surfaces, the concave surfaces en aging said protruding surfaces, the disks belng se-,

cured to said core and held adjacent to said lnassb said disks having central re-entrant portions within which the ends of the core are contained.

4: In a wound bobbin the improvement which consists in a mass ofthread wound upon a tubular core and havinga protruding end surface between the core and its periphery, and disks having annular concavo-convex surfaces, the concave surfaces engaging said protruding surfaces, the disks being secured to said core and held adjacent to said mass, said disks having re-entrant portions within which the ends of the core are contained, said disks having attened zones adjacent to the core.

5. In a wound bobbin the improvement which consists in a mass of thread Wound upon a tubular core and having end surfaces between the core and its eripherj1 protruding beyond the portions jacent to the core and the periphery, and disks having annular concave surfaces engging said proing secured to said core and held adjacent to said mass, and curved externally so that a plane surface resting on the outer portion of either disk contacts therewith only at points radially spaced away from said core and said periphery.

In testimony whereof, I have signed my name to this specification this first day of February, 1926.

. MALCOLM CURRY. 

